Intensity Dependent Photoconductivity in ZnO Nanostructured Film

Abstract

Many studies on the Photoconductivity of ZnO have been performed with an indication of reliable optical application due to fast photo response. This paper reports study of intensity dependent photoconductivity in ZnO nanostructured thin film with a thickness of 800 nm. ZnO nanostructured thin film on ultra clean glass substrate has been deposited using sol-gel spin coating technique. Conductivity at various illumination intensity has been measured using two probe method and found that photoconductivity increases by increasing illumination intensity. Photoconductivity can be utilized in the devices fabrication which are based on the decrease in the resistance of certain materials when they are exposed visible radiation. Photosensitivity and persistent photo conductivity also found to be increasing with illumination intensity. Photo sensitivity enhancement in Nanostructured ZnO is expected due to its large surface to volume ratio which is fundamentally more suitable for optical devices application. Persistent photoconductivity in the ZnO nanostructure thin film can be utilize in memory device applications.